Piano Sonata No.30 in E major Opus 109 Ludwig Van Beethoven
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Cutting-edge sounds: what is classical music's iPhone 5?
Neatly, Mahler specified a solo violin to be tuned a whole tone above the normal pitch to give the 'Dance of Death' in his ninth symphony the necessary eerie quality. It's not so much a music technology innovation as using what was available for a different effect. A bit like putting potato waffles in the toaster.